FIG 1.

PRRSV externalizes PS on the envelope. PRRSV-2 strain BJ-4, HP-PRRSV strain HN07-1, and PRRSV-1 strain GZ11-G1 were shown to expose PS by FCM (A, C, and E) and dot blotting (B, D, and F). MARC-145 cells were inoculated with PRRSV (MOI = 10) at 4°C or PBS as an unbound control. Then, PS was assessed to PRRSV-bound or unbound cells by FCM immediately using annexin V-conjugated Alexa Fluor 488. Each experiment was independently performed three times with similar results, and data from one representative experiment are shown in panels A, C, and E. Dot blot assays were set up with anti-PS 1H6 MAb or anti-PRRSV GP5 MAb as the primary antibody. Twofold dilutions of purified PRRSV in PBS were applied for PS and PRRSV GP5 detection, respectively. PBS was spotted onto samples as a negative control.